calibre is an e-book library management application with a variety of useful functions including device-specific e-book conversion, news download and conversion, viewer and content server for online access to your collection.

@bzl333 weel, you have to bear criticism if you want to improve! (unkind criticism is another matter)Calibre is "huge" (maybe it have to be like that, it's not a criticism, it's just a pity!), and I too don't like at all its way to make its own library (I have to put there only books I want to convert, and remove them, not a user friendly behaviour). It's a little too complicated, but it does its job well!For me it's a must-have but also a could-be-better!! :-)

Sigil is a tabbed editor for the EPUB format commonly used in eBooks. The program includes basic formatting, customizable fonts and styles, hotkeys and spellcheck. You can generate a table of contents, embed files (audio, video, or other), edit/add metadata, rearrange or split pages, add vector (SVG) images and available "clips" for frequently entered text.

As the format is based on simple HTML, the program includes a WYSIWYG-style book vs. code view, the ability to modify cascading style sheets and additional functionality via plugins. The program can even shrink some eBooks by discarding unused media elements.

Cross-platform with clients for Linux, Mac and supports many languages. Sigil Portable is a wrapper version of the program and X-Sigil is also available.

TEBookConverter is an easy to use ebook converter built using calibre. The program has simple conversion interface rather than calibre's ebook management suite and elaborate feature-set. You can convert ebooks quickly and easily using parallel processing.

I was able to successfully convert a DOCX file to MOBI file for an Amazon Kindle device. All I really needed was the index and basic formatting preserved and that's what it did. Also images worked well. I'm very happy.

ReadThemAll is a e-book reader primarily designed to be used in a hand-free mode. Although it can be used as a general purpose reader, its main benefits come from its innovative auto-scrolling: a way of reading books so you don't have to manually list pages.

The program is a successor of the identically named software for PalmOS.